<!DOCTYPE html>
<html>
    <head>
     <meta charset="UTF-8">
      <title>Document</title>
      </head>
       <body> 
        <script>
    var arr = ['新闻摄影','音乐鉴赏','话剧表演','古典诗词','营养与健康','音乐鉴赏','话剧表演'];
    	function course (arr) {	
    	var newArr = [];	
    	for (var i = 0; i < arr.length; i++) {	
            if (newArr.indexOf(arr[i]) === -1){
    	newArr.push(arr[i]);
    }
}    
    		return newArr;
}
    
    	console.log(course(arr));	
    </script>
    </body>
</htm1>